The health of adolescents has recently become an issue of intense national concern. Measurement of adolescent health status is particularly challenging because of the relatively low prevalence of serious medical disorders; low rates of functional limitations; requirements for age-appropriate assessments; and the unknown accuracy of information obtained from adolescents. The available adolescent health status instruments are narrowly focused, limiting the possibility for detecting unexpected health effects and of documenting interrelationships between aspects of health. An optimal health status instrument for describing adolescent health would be characterized by: (1) a unified conceptual framework; (2) comprehensiveness; (3) a broad range of concepts, including positive aspects of health; (4) reliable and valid scales developed for their ability to discriminate health states; and, (5) feasibility of administration. The current proposal is designed to meet these requirements in the development of the Child Health and Illness profile (CHIP). Preliminary studies indicate that the CHIP is sensitive to the wide range of functioning and health attributes that characterize adolescents. Initial studies of its psychometric properties and validity are encouraging and provide a sound basis for further work to establish internal reliability and construct validity. While the pretest results indicated that the instrument was feasible to administer and that initial reliability and validity were promising, they also indicated a need to revise some of the domains. The purpose of this project is to develop a comprehensive health status measure for self-administration by adolescents. The specific aims are as follows: 1. To assess the internal consistency reliability of the various measures of the subdomains and domains that have been developed in preliminary studies. 2. To assess the construct validity of the instrument using concurrent design in representative samples of adolescents in schools and clinical settings. The research outlined in this proposed project will result in the development of a well-tested health status measure that will capture a comprehensive range of attributes related to health, well-being, and functioning in adolescents. The resulting instrument will enable researchers and evaluators to examine health status broadly by means of a self-administered instrument that will serve at least as a standard core in outcomes and health status measurement. The instrument should find immediate use in surveys to document the states of health of populations and subpopulations and changes in health of these populations over time, either as a result of major policy changes or as a result of large-scale health services interventions. The availability of a well-validated instrument will facilitate subsequent testing of usefulness for other purposes such as a screening, ascertaining individual change resulting from medical interventions and exploring relationships between aspects of health and their impact on future function and well-being.